static new Flag startDeadlockDetector_started;
static int startDeadlockDetector_interval;

static void startDeadlockDetector() {
  if (startDeadlockDetector_started.raise())
    doEvery_daemon(1000, func {
      if (empty(printDeadlocks())) null;
      print("Stopping deadlock detector.");
      false;
    });
}